i would use the firstname.lastname@example.org address.
remember he gets tons of people wanting slot machine glass, shuffle alley glass, all kinds of wacky glass requests. if it's not pinball, chances are pretty good you won't hear back. the reason for this is simple... if steve makes one of any glass, he's loosing money/time in a big way. he needs to make three of a particular glass before he even breaks even. so if you're requesting some wacko game that essentially only you own, then he's just not going to do it. There are so many other people asking for glasses that will help a lot more machines. so that lower hanging fruit will get done before some one-off thing. steve's mission in life isn't to help you with some weirdo 1950s game only you happen to have. it's a bigger picture he's trying to help. and the one-off stuff is just a huge time suck with no payoff.
the only exception to this rule is basically if you know steve personally, and he's doing you a favor. or you do the artwork. (get it scanned at 300 dpi, scaled correctly, and then you do the photoshop work and the pantone color correction.) because it's not the printing of the glass that takes the huge time (though making a glass is a several hour operation), it's the photoshop work that takes all the time. And if the glass is in bad shape to start, then the time involved ramps up quickly.